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What is a Behind the Meter System ?

A Behind the Meter system ( BTM ) is a Renewable Energy system uniquely designed and bult for a single building or facility.  Its purposes are :
  • to reduce the carbon footprint of the building by generating electricity 'locally' from renewable sources
  • to reduce the amount of electricity purchased by the building ( typically reducing the electrical bill by about 80% )
  • to take the structure "off the grid" for some or all of the working day
  • to provide power conditioning and UPS characteristics for the whole building
  • to eliminate blackouts to the building, providing uninterruptable power during grid failures
  • to eliminate the damaging effects of brownouts on the building
  • to buy electricity at the lowest possible purchase rates
  • typical payback is 8 years
  • Click Here to see details
  • Click Here to see a  typical Behind the Meter system


A BTM consists of the following compnents :
  • a solar array to capture energy from sunlight
  • a number of wind turbines to capture wind energy
  • a storage system to store electricity from the RE components and any purchased from the grid
  • a control system to manage the production, storage and delivery of the electricity

How does a BTM work ?

Currently, your building has a single source of energy - the grid ( excluding backup generators )

Because you are limited to that single source, you are exposed to :

  • whatever price structure is imposed on you by your jurisdiction
  • whatever blackouts your location experiences
  • whatever brownouts happen in your location
  • random and destructive power 'spikes' that can affect or even destroy electronics

A BTM allows you to access electricty from :

  • Renewable Energy sources ( typically both wind and solar )
  • the grid ( as backup )
  • energy stored within the Battery Storage of the BTM

The BTM operates as a large UPS within your building, charging its batteries from renewables, and buying any extra energy as needed from the grid.

Because the BTM's smart controller is constantly monitoring all the energy sources as well as the load being drawn, it can :

  • constantly determine the amount of electricity being drawn
  • constantly determine the amount of electricity being generated
  • constantly determine the 'state of charge' of the storage system
  • know how your load normally varies with time ( for example, you may have a lower load evenings and weekends )

Using this information, the BTM does the following :

  • constantly receives energy from the Renewable Energy sources ( unless it is both dark and windless ) to charge the batteries
  • supplies energy from the storage system directly to the load ( the equipment within your building )
  • if necessary, buys electricity from the grid when the grid supply price for electricity is at its lowest

Although technologically it can do so, a BTM normally does not sell power back to the grid  it uses all the power for its host building. 

In jurisdictions like Ontario that have a Feed In Tarrif, it is generally forbidden to have a single system that both sells electricity to the grid and also uses it internally.

Depending on your jurisdiction, it may be practical to have a dual purpose system.